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1. The big picture
When do people act, and how do games create those conditions?
Fogg Behavior Model (B=MAP)
A behavior happens when motivation, ability, and a prompt meet at the same moment.
Practitioner framework
Self-Determination Theory
People keep going on their own when they feel autonomy, competence, and relatedness.
Well supported
Flow
People become absorbed when challenge matches skill and goals and feedback are clear.
Well supported
MDA Framework
Think of a game as three layers: mechanics the designer sets, dynamics that emerge in play, and aesthetics the player feels.
Practitioner framework
Octalysis (8 Core Drives)
A framework that splits what drives people into eight forces, so you can see which ones a design relies on.
Practitioner framework
Hook Model
A product model where cycling through trigger, action, variable reward, and investment turns use into habit.
Practitioner framework
Does gamification work?
Gamification is using game design elements outside games. Average effects are small to moderate and depend heavily on context and design.
Contested
2. Rewards and curiosity
When do rewards and curiosity move people, and when do they backfire?
Variable reward
When rewards arrive unpredictably, people repeat the behavior more.
Well supported
Overjustification effect
Adding contingent rewards to something people already enjoy can make them stop doing it once rewards end.
Contested
Information gap theory
A small gap between what people know and want to know makes them want to close it.
Well supported
Goal-setting theory
Specific, challenging goals lead to better performance than "do your best."
Well supported
IKEA effect
Things people build themselves feel more valuable than the same things made by others.
Limited evidence
Loss aversion
A loss tends to feel bigger than a gain of the same size.
Contested
3. Progress and momentum
Why do people who start keep going to the end?
Goal-gradient effect
People speed up as they get closer to a goal.
Well supported
Endowed progress effect
Starting people partway along makes more of them finish.
Limited evidence
Unfinished tasks (Zeigarnik and Ovsiankina)
People tend to return to interrupted tasks. The famous claim that unfinished tasks are remembered better did not hold up in a meta-analysis.
Contested
Peak-end rule
People judge an experience mostly by its most intense moment and its end, not its average.
Well supported
4. Less effort, clear feedback
How much do effort and response speed shape behavior?
Fitts’s law
The farther and smaller a target is, the longer it takes to hit.
Well supported
Response-time limits
Under 0.1 seconds feels instant, under 1 second keeps the flow of thought, and over 10 seconds loses attention.
Well supported
Choice overload
Too many options can stall decisions or lower satisfaction, but whether it happens depends heavily on conditions.
Contested
Default effect
Options that are preselected tend to stay selected.
Well supported
Labor illusion
Seeing the work behind a result makes it feel more valuable, even with a wait.
Limited evidence
Game feel
When motion, sound, and light answer an input instantly and pleasantly, touching becomes fun in itself.
Practitioner framework
5. Other people
How do other people, commitments, and gifts change decisions?
Social proof
When unsure, people look at what others do to decide.
Well supported
Social comparison and leaderboards
People judge their abilities against others. Leaderboards can draw out effort and can also deflate motivation.
Contested
Commitment and consistency (foot in the door)
People who agree to a small request are more likely to agree to a larger one later.
Contested
Reciprocity
Receiving something makes people want to give back.
Well supported
Scarcity
Things that are scarce or about to expire look more valuable.
Well supported